After the cure properties were measured (Table II), the rubber compounds were cured in a compression mold at 160C and a pressure of 160 atm. Pieces of rubber, each approximately 57 g in weight, were cut from the milled sheet. Each piece was placed in the center of the mold to enable it to flow in all directions when pressure was applied to prevent anisotropy from forming in the cured rubber. For determining the mechanical properties of the rubber vulcanizates, sheets 15 cm by 15 cm in dimensions and 2.3 mm thick, were cured from which various samples for further tests were cut